Carbohydrate monoesters, and specifically sucrose monoesters, are used commercially as food emulsifying agents, as coating agents and as excipients in pharmaceutical, cosmetic and other products. Commercially available monoesters, typically made by chemical means, comprise mixtures of positional isomers or are often mixed with an amount of di- and tri-esters (usually at about 20% of the mixture). However, there is no commercially feasible synthesis that selectively yields pure monoesters, that is monoesters which substantially comprise one positional isomer of a monoester such as the 6-O, 6'-O or 1'-O monoester. If commercially available mixtures made by chemical means could be resolved such that specific isomers of the monoesters could be isolated, it would be advantageous since by selective isolation of the isomers the monoesters may have unique properties for food and cosmetic uses compared to the mixtures.
Therefore, there is a need for a process for the resolution of regio-selective isomers of carbohydrate monoesters, and particularly sucrose monoester. It is an object of this invention to provide a method to resolve a mixture of carbohydrate monoesters obtained by chemical reaction into monoesters of defined structure which comprise substantially the 6-O-ester, the 1'-O-ester or the 6'-O-ester.